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gst/matroska/ebml-read.c: Prevent unaligned memory access when reading floats.
Original commit message from CVS: * gst/matroska/ebml-read.c: (_ext2dbl), (gst_ebml_read_float): Prevent unaligned memory access when reading floats.
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2 changed files with 17 additions and 20 deletions
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@ -1,3 +1,8 @@
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2008-06-15 Sebastian Dröge <slomo@circular-chaos.org>
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* gst/matroska/ebml-read.c: (_ext2dbl), (gst_ebml_read_float):
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Prevent unaligned memory access when reading floats.
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2008-06-15 Sebastian Dröge <slomo@circular-chaos.org>
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* gst/matroska/ebml-read.c:
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@ -24,6 +24,7 @@
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#endif
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#include <string.h>
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#include <gst/floatcast/floatcast.h>
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#include "ebml-read.h"
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#include "ebml-ids.h"
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@ -692,21 +693,24 @@ struct _ext_float
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static gdouble
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_ext2dbl (guint8 * data)
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{
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struct _ext_float *ext = (struct _ext_float *) data;
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struct _ext_float ext;
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guint64 m = 0;
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gint e, i;
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memcpy (&ext.exponent, data, 2);
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memcpy (&ext.mantissa, data + 2, 8);
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for (i = 0; i < 8; i++)
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m = (m << 8) + ext->mantissa[i];
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e = (((gint) ext->exponent[0] & 0x7f) << 8) | ext->exponent[1];
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m = (m << 8) + ext.mantissa[i];
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e = (((gint) ext.exponent[0] & 0x7f) << 8) | ext.exponent[1];
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if (e == 0x7fff && m)
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return 0.0 / 0.0;
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e -= 16383 + 63; /* In IEEE 80 bits, the whole (i.e. 1.xxxx)
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* mantissa bit is written as opposed to the
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* single and double precision formats */
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if (ext->exponent[0] & 0x80)
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if (ext.exponent[0] & 0x80)
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m = -m;
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return ldexp (m, e);
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}
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@ -739,27 +743,15 @@ gst_ebml_read_float (GstEbmlRead * ebml, guint32 * id, gdouble * num)
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if (size == 4) {
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gfloat f;
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#if (G_BYTE_ORDER == G_BIG_ENDIAN)
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f = *(gfloat *) data;
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#else
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while (size > 0) {
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((guint8 *) & f)[size - 1] = data[4 - size];
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size--;
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}
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#endif
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memcpy (&f, data, 4);
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f = GFLOAT_FROM_BE (f);
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*num = f;
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} else if (size == 8) {
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gdouble d;
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#if (G_BYTE_ORDER == G_BIG_ENDIAN)
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d = *(gdouble *) data;
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#else
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while (size > 0) {
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((guint8 *) & d)[size - 1] = data[8 - size];
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size--;
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}
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#endif
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memcpy (&d, data, 8);
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d = GDOUBLE_FROM_BE (d);
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*num = d;
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} else {
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